How to build a kitchen timer?

One of those things you can set to for example 8 minutes so that it beeps when your pasta is finished.

You need:

* a display to show the time
* some buttons to set the time and start/stop the timer
* a buzzer to create sound when the timer finished
* a microcontroller to control the display, detect button press, and keep track of time

Since we only need numbers, a good type of display to use is a 7-segment LED display.

It’s easy to control, and usually pretty cheap.

The buttons can be standard tactile pushbuttons.

And an active buzzer makes the sound turn on with just a high output from the microcontroller.